Closure device for headers



June 12, 1934. R. K. HOPKINS CLOSURE DEVICE FOR HEADERS Filed Aug. 19.1932 N INVENTOR N Zafier/ Z fig 41 Patented June 12, 1934 UNITED STATESPATENT OFFICE 7 1,962,901 CLOSURE DEVICE ron HEADERS ware ApplicationAugust 19, 1932, Serial No. 629,431 7 Claims.

This invention relates to headers or return bends, and relates moreparticularly to closure devices for headers or return bends.

The primary object of the present invention 5 is to provide a closurefor a header or return bend so constructed as to be practicallyincapable of improper placement or fastening, whereby a tight closuremay be readily obtained and the security of operation increased.

A further object of the invention resides in the provision of aself-centering securing means for such closure devices.

A still further object is to provide an improved form of deflector plugthat cannot be incorrectly mounted in the header or return bend.

Other objects and advantages of my invention will be apparent from thefollowing description, taken in conjunction with the accompanyingdrawing, which forms a part of this specification, and in which:

Figure 1 is a side elevation, partially in central vertical section, ofa header or return bend embodying my invention;

Figure 2 is a front elevation partially in section, taken on the line2-2 of Figure 1;

Figure 3 is a detail view of a part of the structure shown in Figures 1and 2;

Figure 4 is an end elevation, partially in section, of a modified formof my invention;

Figure 5 is a front elevation of a still further modification; and

Figure 6 is a central vertical section taken on the line 66 of Figure 5.

Referring more particularly to the drawing, there is shown in Figures 1and 2 a header or return bend 10 having a body portion 11 containing twotube bores 12 and 13, having tube seats 14 and 15, respectively, and across-over connection 16 between the tube bores. Opposed ears 17 and 18are provided on the body portion 11 above each of the tube bores. Withthe exception of the dimensioning of the ears 1'7 and 18, to be referredto hereinafter, the construction of the parts so far described is moreor less conventional. The body 11 of the header or return bend may bemade by casting in the usual manner, or preferably by welding twoindividual forgings together at 19 as disclosed in my copendingapplication Serial No. 655,719, filed Feb. 8th, 1933.

As shown more particularly in Figure 2, the ears 1'7 and 18 are soproportioned that the two slots 20 and 21 formed between the edgesthereof are of unequal width, the slot 20 being shown as substantiallywider than the slot 21. Plugs 22 are adapted to close the upper ends ofthe tube bores, fitting tightly against the machined seats 23 in thebody 11 of the header. Each plug 22 is provided with two opposed ears 24and 25, adapted to fit in the slots 20 and 21, respectively. As shown inFigure 2, the ear 24 is wider than the ear 25, so that the ear 24 willfit Within the slot 20, but cannot be inserted in the slot 21.Consequently, in inserting a plug, 22 in a plug seat 23, the plug can beinserted only in one position. The plugs 22 are shown as being of thewell known deflector type. It is imperative that deflector plugs beinserted in the correct position, as otherwise the cross-over channel 16would be very largely blocked by the curved surface of the plug. 01"course, when using ordinary plugs having their lower surfacesubstantially flat, it is unimportant in which direction the plug may beinserted. For plugs of the latter type, therefore, the cars 24 and 25and the slots 20 and 21 may be so proportioned that either ear may fitin either slot.

For the purpose of holding each'plug 22 firmly against its seat 23,there may be employed a yoke 30 having arms 31 and 32 fitting into holes33 and 34 in the ears 1'? and 18;"respective1y. A screw 35 is threadedinto the center of the yoke 30, and engages the center or" the plug 22.By tightening the screw 35, the yoke 30 is raised so that the arms 31and 32 engage the upper ends of the holes 33 and 34, respectively,thereby causing the lower end of the screw 35 to press against the plug22 and hold it firmly in place.

With yokes of this character as commonly employed heretofore, it hasbeen possible for the lower end of the screw 35 to be seated at somepoint other than thecenter of the plug 22. This has occasionallyresulted in slippage of the plug 22 when in use under high pressure,thereby causing leakage and danger of fire. In order to avoid thiscontingency, I provide means for insuring the centering of the screw 35on the plug 22.

As shown more particularly in Figure 3, the lower end of the screw 35 isrounded to form a tip 36 having the contour of a segment of a sphere. Arecess 37 is machined into the center of the top of the plug 22, thebottom or seat 38 ofthe recess being spherically shaped to conform tothe tip 36 of the screw 35, and the upper portion or approach 39 of therecess being preferably in the form of a frustum of a cone having itslower end substantially equal in area to the area of the seat 38 and itsupper end considerably larger than the seat 38. If the screw 35 no yoke30, are vertical.

of the yoke.

'34 of corresponding widths.

be tightened when its spherical tip 36 is within the conical approach39, the yoke will be raised as the tip 36 engages in the conicalapproach 39, and at the same time, the screw will move toward the centerof the recess 3'7 until the tip 36 is seated firmly in the sphericalseat38 This construction of thescrew 35 andthe; recess 37 insuresaccurate centering of the screw 35 on the plug 22. The accuracy of thecentering depends upon the accuracy of the correspondence of thediameter of screw tip 36 and the diameter of the spherical seat 38, thusby takingc-thernece essary care in the making of screw tip 36 andspherical seat 38 an accuracy of centering well beyond anythingheretofore attainable is possible. Because of the slope of conicalapproach 39 tip 36 will not grip and bind but will move down conicalapproach 39 to spherical seat 38,

thus centering itself as Well as the whole of screw 35 relative to plug22. This centering of screw 35 is made possible by the fact thatarms 31and 32 or" yoke 30 slide relative to cars 17 ande18 astip 36 moves downconical approach 39 and allows screw. 35 to move to the centeringposition. It will be understood. that the approach .39, instead of beingconical, might be made as a continuation of the, spherical surface ofthe seat 38, or in some other form. The im portant thing, is that theapproach 39. should constitute an inclined surface adapted to guidetheflscrew 35. toward the seat 38. Similarly, the tip 36. need not bespherical in shape, but may have anyv contour adapted to slide along theapproach 39, the seat 38 having preferably. the same. contour as the tip36.

In order that the screw 35 may atall times be presented to the plug 22withinthe conical approach 39, I providea stop 40 on the yoke arm 32.This stop 40 is adapted to engagev the innerwall of the car 18, andthusroughly centersthe screw 35. above the conical approach 39. It willbe understood that headers of. this. character are usually mounted on astill in the position shown in Figure 2, in such manner that the armsofv the Obviously, the stop. 40 cannotserve to center theyoke 30unlessthe stop 40. isin engagement with the inside wall of. the earcoacting therewith, This engagement will be provided automatically bygravity due, to the weight of the yoke 30, which is quite considerable,

if, the yoke be inserted in such manner ,that the arm carryingthe yokestop 40 is the lower arm According to my inventiornl preferablycorrelate the dimensions of the yoke arms and their cooperating holes inthe ears 1'7 and 18,

sothat the yoke 30 can only be inserted with the stop 40 in the desiredposition. I

In the modification of my invention shown in Figures 1 and 2, Iaccomplish this latter result by making one of thearms of the yokenarrower than the other arm,an d making the slots 33and As shown inFigure 2, the arm 31 and its cooperating slot 33 are made narrowerthanthe arm 32 and the slot 34. It will be obvious, however, that either armcouldbe thewider one, provided the slots 33.and 34 were correspondinglyarranged so that the yoke stop 40 would always be on the lower arm.

In Figure 4, I disclose a modification in which the same result isaccomplished in a somewhat different fashion. In this figure, the yoke30 is constructed similarly to the yoke 30 shown in Figure 2, exceptthat the two arms 31 and. 32' are symmetrical, aside from the locationof the stop 40' on the arm 32*. The yoke holes 33' and 34' are locatedin the ears 17 and 18 respectively, and are adapted to cooperate withthe arms 31' and 32, respectively. The yoke holes 33' and 34' may be ofthe same width, but as shown in Figure 4, the yoke hole 33 has a heightgreater than that ofthe .yokehole 34. In insertingthe yoke,itisnecessary to slide one of the. arms through its yoke holeconsiderably past the center position, and then tilt the yoke and moveit backward so that the other yoke arm enters its aperture. With thedimensioning of the yoke arms 31 and 32 andthe holes 33' and 34 shown inFigure 4, it will be apparent that the yoke 30' can only be inserted byintroducing the arm 31' into the aperture 33'.- If it were attempted toreverse the yoke, the rounded bottom portion of the yoke would strikeagainst the bottom of the aperture 34' before the insertion of the yokecould be completed.

It will be obvious that the yoke constructions shown in Figures 2 and 4are therefore irreversible in character, so that the yoke can only be,inserted in such position that the force of gravity insures properengagement of the yoke stop with the cooperating ear. I have thusobviated the possibility of a careless workman, in replacinga yoke aftercleaning, failing to center the. yoke so that the screw 35- will enterthe self-centering conical approach 39.

In Figures 5 and 6.1 have shown the self-centering feature of myinvention as applied to a modified form of header closure. The.closuredevice shown in these figures is of the wellknown set collartype. The header 50.;is provided witha plug seat 51 which is closed by aplug 52. A counter bore 53 is formedin the upper portion of the headerand is cut away as shown at54tto permit the entrance of a set collar 55and the plug 52. The plug 52 may be provided with a lug 56 to facilitateits insertion and removal. A screw57 is'threaded into the center ofthecollai' 55 and isadapted to engage the plug 52. 'The collar 55 isprovided with .a shoulder 58.. which engages the upper side ofthecounter bore 53 and provides the necessary fulcrum to permit tighteningof the screw 5'? against the plug .52.

According to my invention, I provide the screw 57 with a rounded tip. 60and the plug 52 with a self-centering recess 61, exactlysimilar to the.tip 36 and recess 37 shown in Figure 3 and described above in connectionwith other embodiments .of

.my invention. In order to insure the entry of the screw 57 within theconical approach .62 of the recess 61, I make the collar 55 and thecounter bore 53 of such dimensions that the collar 55 can move withinthe. counter'bore only to an extent which will not permit the screw .57to get outside of the range of the conical approach 62. It will thus beapparent that the correlation of the collar 55 and the counter bore 53performs the same function as the yoke stop 40shown in Figure 2.

It will be obvious to those skilled in the ar't that many modificationsand changes may be made in .my invention without departing from thespirit thereof, and I desire to bellimited, therefore, only by thepriorart and the scope of the appended claims. I claim:

1. A closure device for a header comprising a plugadapted to fit tightlyin a seat in the-header, a recess formed in the outer face ofsaidplug,said recess having 'a screw seat and an approach thereto soinclined that when a screw tip is urged thereagainst said screw tip willmovedown said approach to said screw seat, a positionable yoke adaptedto bear against a portion of the header, a screw threaded in said yoke,said screw having a tip of substantially the same diameter as said seat,means on said yoke adapted to cooperate with said header to positionsaid yoke with said screw tip in approximate alignment with said screwseat within said inclined approach, said yoke being slidable relative tosaid header whereby when said screw tip is urged against said approachsaid yoke will move relative to the header to permit the lateralmovement of the tip required to seat said tip in said screw seat.

2. A closure device for a header comprising a plug adapted to fittightly in a seat in the header, a recess in the outer face of saidplug, said recess having a screw seat and an approach thereto soinclined that when a screw tip is urged thereagainst said screw tip willmove down said approach to said screw seat, a yoke having arms adaptedto fit in apertures in the sides of the header, a screw threaded in saidyoke having a tip of substantially the same diameter as said screw seat,a stop on one of the arms of said yoke adapted to cooperate with theheader to position said yoke with said screw tip in approximatealignment with said screw seat and within said inclined approach, saidarms of said yoke being slidable in said apertures whereby said yokemoves relative to said header to accurately align said screw with saidscrew seat said screw tip is urged down said inclined approach.

3. A closure device for a header comprising a plug adapted to fit in aseat in the header, a recess in the outer face of said plug, said recesshaving a screw seat and an approach thereto so inclined that when ascrew tip is urged thereagainst said screw tip will move down saidapproach to said screw seat, a yoke having arms adapted to fit inapertures in the sides of the header, a screw threaded in said yokeadapted to seat in said screw seat, a stop on said yoke adapted toengage the header to position said screw in approximate alignment withsaid screw seat and within said approach, said yoke being soproportioned with respect to said header apertures as to be capable ofinsertion in the header in only one direction.

4. A closure device for a header comprising a plug adapted to fittightly in a seat in the header, a recess formed in the outer face ofsaid plug, said recess having a screw seat and an approach thereto soinclined that when a screw tip is urged thereagainst said screw tip willmove down said approach to said screw seat, a yoke having arms ofunequal width adapted to fit in apertures in the header walls, a screwthreaded in said yoke having a tip of substantially the same diameter assaid screw seat, and a stop on one of said arms adapted to engage theheader walls to position said yoke with said screw tip in approximatealignment with said screw seat and within said inclined approach,whereby when said screw is screwed towards said plug and said screw tipmoves down said inclined approach to said screw seat said yoke will moverelative to the header walls as required to accurately align said screwand screw tip with said screw seat. A

5. A closure device for a header comprising a plug adapted to fit in aseat in the header, a recess formed in the outer face of said plug, saidrecess having a seat for a screw and an inclined approach thereto, ayoke having arms adapted to fit in apertures in the sides of the headerand a screw threaded in said yoke with its end adapted to seat in saidscrew seat, said yoke being so proportioned with respect to the headeras to be capable of insertion in the header in only one direction andsaid inclined approach being disposed at such an angle as to assurevuponurging of said screw against said inclined approach the alignment ofsaid screw with said screw seat by reason of the movement of said screwdown said inclined approach and the movement of said yoke and screwtowards the center of said screw seat, whereby said screw will be causedto engage the plug at the screw seat when the screw is turned into tightengagement with the same.

ROBERT K. HOPKINS.

